New drum problems

trucker1

Junior Member
Has anyone bought new brake drums that the center opening was too small to fit the hub, even a press fit. Would it be best to have a machinist open it up rather than cut down the shoulder of the hub? Thanks in advance.
 
What car are you working with? A while ago, I bought some rear F150 drums to be used on F1 front hubs. There were two different versions of the drums with different diameters of the center hole. I bought them from Rock Auto. Their information includes all of those dimensions.
 
I have 40 style with the hubs behind the drums and they came from macs antique parts. I hope I didn't bend anything trying to pull them together. The labor to bore these drums is as much as a new one. There seems to be a lot of junk that doesn't fit in this hobby. When we tried to cut down the inner lip to use on a Model A axle the machinist said the hub was bent but it wasn't seated under the drum. Thanks for the reply. Glynn.
 
Sounds like possibly a couple of problems here. First possible problem......I would never buy a brake drum from Mac's.

Secondly, you say '40-type brake drums and hubs. You also said something about bent hub. How did you separate the original drums from the hub? If you tried to press, or hammer the studs out of the hub, that is when it got bent. The factory studs are swedged once the drum is installed. This physically changes the shape of the steel stud to hold the stud in, and to lock the drum on. The only way to properly remove the five studs (and the drum) is to use a cutter to cut the swedge away from each stud. If you hammered or pressed them out, you've most-likely ruined your hubs. If it makes you feel ANY better at all, I learned this the hard way almost fifty years ago.

GOOD quality drums are out there. Cheap, junk drums are out there also. Type "MT Car Products" into your browser for GOOD drums and hubs and associated, requisite parts. Hope this helps! DD
 
I cut out the swedge with the correct cutter but a machine shop tried to swedge new studs but ruined one drum. I converted it to press in configuration as per Dick Spadaro's instructions. When I took them to cut down the inner lip to fit the Model A axle it wobbled so he said the hub was bent. After pressing out the studs I noticed the drum wouldn't seat because the hole is about 1/16" too small. That would make it wobble. I'm taking the separate parts to spin on a brake drum cutter to see if any of this is bent. I should have noticed the difference in size but learned the hard expensive way. Thanks for the help, Glynn.
 
Like V8 said. Buy 2 new MT Products drums and hubs. Use your old original rear wheel bearings but get new seals. The drums come in 1 3/4 in. and 2 in. width. Your OEM brake shoes are probably 1 3/4 in. Not cheap but great quality. The MT drums have lots of metal for turning later on, if needed. They can be cut .090 over. Most drums are .060 max. It's really nice not having to use a KR Wilson wheel puller anymore. I have them on my 40.
 

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Were there not 2 diff size holes in the brake drums depending on year originally??
Paul in CT

Yes, 3 1/4" on '39-'42 and 4" on the '46-'48, the later hubs mount externally on the drum. I may be off a year on the early drum, was the year of transition 1941 rather than '42?
 
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